Near net shape manufacturing of magnets with photosensitive slurry

Abstract

A magnet and a method of forming the magnet are provided. The method includes forming a slurry comprising magnetic powder material and photopolymerizing material and creating raw layers from the slurry. Each layer is cured by electromagnetic radiation prior to forming another layer on the most recent cured layer. The layers are attached together. The method may also include applying a magnetic field to each raw layer while curing the layer, to orient the magnetic powder material in a desired direction.

1 . A method of forming a magnet, the method comprising:
 forming a slurry comprising magnetic powder material and photopolymerizing material;   creating a raw first layer from the slurry;   curing the raw first layer with electromagnetic radiation to form a cured first layer;   after curing the raw first layer, creating a raw second layer from the slurry in contact with the cured first layer; and   curing the raw second layer with electromagnetic radiation to form a cured second layer, the cured second layer being attached to the cured first layer.   
     
     
         2 . The method of  claim 1 , further comprising applying a magnetic field to the raw first layer while curing the raw first layer, and applying a magnetic field to the raw second layer while curing the raw second layer, to substantially orient the magnetic powder material in a desired direction. 
     
     
         3 . The method of  claim 2 , further comprising disposing a plurality of additional layers, layer by layer, onto the cured second layer, each additional layer being formed from the slurry, and in between disposing each additional layer, curing with light a most recent disposed additional layer to form a plurality of attached cured layers. 
     
     
         4 . The method of  claim 3 , the slurry further comprising an organic-based solvent. 
     
     
         5 . The method of  claim 3 , wherein the electromagnetic radiation is visible light. 
     
     
         6 . The method of  claim 5 , further comprising providing the visible light with a light-emitting diode (LED). 
     
     
         7 . The method of  claim 6 , further comprising:
 providing a base;   providing a vat holding the slurry;   lowering the base toward the slurry to dispose the raw first layer onto the base prior to curing the raw first layer;   lifting the base after curing the raw first layer;   removing residual slurry;   applying a second fresh layer of the slurry by scrubbing with a knife;   lowering the base toward the slurry to dispose the raw second layer onto the cured first layer prior to curing the raw second layer; and   lifting the base after curing the raw second layer.   
     
     
         8 . The method of  claim 7 , further comprising disposing the LED below the vat, the vat having one of a translucent bottom and a transparent bottom. 
     
     
         9 . The method of  claim 3 , further comprising:
 sintering the cured first and second layers and the plurality of attached cured layers; and   subjecting the cured first and second layers and the plurality of attached cured layers to a hot isostatic press (HIP) process,   wherein creating the slurry comprises homogenously mixing the magnetic material and the photopolymerizing material.   
     
     
         10 . The method of  claim 3 , further comprising:
 providing the slurry as having a viscosity of at least 3 Pascal-seconds; and   providing the magnetic field in the range of 0.5 to 4 Teslas.   
     
     
         11 - 12 . (canceled) 
     
     
         13 . The method of  claim 3 , further comprising providing the magnetic powder material comprising at least one rare earth metal. 
     
     
         14 - 15 . (canceled) 
     
     
         16 . A magnet containing a plurality of layers comprising magnetic powder material, each layer comprising cured photosensitive resin. 
     
     
         17 . The magnet of  claim 16 , wherein the magnet has an anisotropic orientation. 
     
     
         18 . The magnet of  claim 17  comprising at least one rare earth metal, each layer being in the range of 10 to 100 micrometers thick. 
     
     
         19 . The magnet of  claim 18  comprising neodymium, iron, and boron. 
     
     
         20 . The magnet of  claim 19 , further comprising at least one of dysprosium and terbium. 
     
     
         21 . The method of  claim 13 , further comprising providing the magnetic powder material comprising neodymium, iron, and boron. 
     
     
         22 . The method of  claim 13 , further comprising providing the magnetic powder material comprising at least one of dysprosium and terbium. 
     
     
         23 . A magnet formed by the method of  claim 1 . 
     
     
         24 . A magnet formed by the method of  claim 2 .